<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div>
  <h1>{{info}}</h1>
</div>

<script src="http://cdn.staticfile.org/vue/2.2.2/vue.min.js"></script>

<script>
  let v = new Vue({
    el:"body>div",
    data:{
      info:"Hello vue!"
    }
  })
  setTimeout(function (){
    v.info = "值改变了"
  },3000)
</script>
</body>
</html>